Update StandardizationGuidelines.md

Author: nataled

docs/StandardizationGuidelines.md

@@ -41,6 +41,5 @@ title: Ontology Standardization Guidelines
 
 Not yet classified:
 
-- METADATA Versioning term identifiers [#1347](https://github.com/OBOFoundry/OBOFoundry.github.io/issues/1347)
 - METADATA Ontology merging [#1548](https://github.com/OBOFoundry/OBOFoundry.github.io/issues/1548)
 - METADATA Modeling metaclasses [#2454](https://github.com/OBOFoundry/OBOFoundry.github.io/issues/2454)